The Bible, Mere Christianity (C.S. Lewis), the Normal Christian Life (Watchman Nee), the Cost of Discipleship (Dietrich Bonhoeffer), Pagan Christianity/Reimagining Church (Frank Viola), the Lord of the Rings series (J.R.R. Tolkien), the Enders Game/Shadow series (Orson Scott Card), the Belgariad/Mallorean series (David Eddings).